Introduction. Psoriasis is one of the most pressing problems of dermatologists, it accounts for up to 30% of all skin diseases. The study of the pathogenesis of psoriasis is currently due to an increase in the number of severe, disabling forms of the disease. The purpose of the study. To evaluate the prognostic significance of markers of endothelial dysfunction and platelet functional activity in patients depending on the severity of psoriasis. Materials and methods. The study included 80 patients with vulgar psoriasis (40 women and 40 men) with a course of moderate severity (n=33, PASI – 17±5, DLQI-7±2)), and severe (n=47, PASI -30±7, DLQI-16±3). The average age is 48±15 years. Circulating endothelial cells and P-selectin on platelets were determined on an FC500 flow cytometer (Beckman Coulter). Results. In patients with moderate and severe psoriasis, a statistically significant increase in the level of circulating endothelial cells was found (10 [7.5-11.5]/3x105 WBC) and (14 [7.0-19.5]/3x105 WBC), respectively, compared with the control group (3.0 [1.0-5.0]/3x105 WBC), p 0.001. The number of platelets with P-selectin expression (1.9% [1.25-2.65]) in patients with moderate severity and (3.2% [1.5-5.4]) with severe course was significantly higher than in the control group (0,9% [0,7-1,7]). Correlation analysis showed that the level of P-selectin is directly correlated with the level of circulating endothelial cells. To increase the prognostic significance of these laboratory parameters and assess the severity of the condition, a ROC analysis was performed with the construction of ROC curves and the calculation of the area under the curve (AUC). Conclusion. It was found that the level of P-selectin is a more sensitive prognostic marker of the severity of psoriasis, and the number of circulating endothelial cells is a specific prognostic marker for the development of possible cardiovascular outcomes.